Measuring the fracture toughness of single WC grains of cemented carbides by means of microcantilever bending and micropillar splitting

The main goal of this work is to obtain a reliable value of the fracture toughness of single grains of tungsten carbide (WC). It is attempted by testing microcantilever and micropillar samples shaped out, by means of focused ion beam milling, of individual WC particles embedded within a WC-Co cement...

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Detalles Bibliográficos
Autores: Ortiz Membrado, Laia|||0000-0001-9646-3226, Cuadrado Lafoz, Nuria|||0000-0002-3745-2372, Casellas Padró, Daniel, Roa Rovira, Joan Josep|||0000-0002-7440-0766, Llanes Pitarch, Luis Miguel|||0000-0003-1054-1073, Jiménez Piqué, Emilio|||0000-0002-6950-611X
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/353297
Acceso en línea:https://hdl.handle.net/2117/353297
https://dx.doi.org/10.1016/j.ijrmhm.2021.105529
Access Level:acceso abierto
Palabra clave:Fracture toughness
WC grains
Mechanical properties
Micromechanical testing
Metalls -- Propietats mecàniques
Àrees temàtiques de la UPC::Enginyeria dels materials::Metal·lúrgia
Descripción
Sumario:The main goal of this work is to obtain a reliable value of the fracture toughness of single grains of tungsten carbide (WC). It is attempted by testing microcantilever and micropillar samples shaped out, by means of focused ion beam milling, of individual WC particles embedded within a WC-Co cemented carbide grade. Experimental testing included the use of a nanoindenter for inducing microcantilever bending and micropillar splitting, as well as sampling WC grains with basal and prismatic orientations. Experimental results are compared with those previously assessed through implementation of the indentation microfracture technique. Bending of notched microcantilevers yielded more consistent results than those measured out of micropillar splitting tests. In this regard, the average value of fracture toughness for single WC grains, within the two-phase interpenetrated network existing in cemented carbides, is found to be 5.6 ± 0.8 MPa·m1/2. Such a relatively high value – coherent with local plastic features evidenced in nanoindentation imprints - is in satisfactory agreement with results indirectly estimated from other macromechanical tests.